William Hart, a worker at FedEx’s massive regional hub at Los Angeles International Airport, was catching a box from a co-worker and loading it onto a conveyor belt about every three seconds on Cyber Monday, expected to be the busiest day ever for most of the nation’s shipping companies.

“It’s hard work,” said Hart, around 4 a.m. after giving a fist-bump to his manager between loads. “TVs. Videos. We got it all. We even get animals. It (does) feel busier.”

As more holiday shoppers flock to online emporiums such as Amazon.com, holiday shipments via the nation’s largest carriers — the U.S. Postal Service, UPS and FedEx — are expected to hit record levels.

FedEx, spurred by online cash cows like Amazon.com, expected this Cyber Monday to hit 22 million shipments worldwide — double its busiest day six years ago and twice its off-season daily average.

That’s an 11 percent spike over last season’s busiest day.

To handle the load, the Memphis, Tenn.-based shipping company hired 20,000 seasonal workers, including 1,200 in Southern California, mostly for FedEx Ground delivery.

Company officials attribute the spike to a growth in global online purchases it says far exceeds the growth rate of local stores. While national holiday sales at stores and online were expected to grow 3.9 percent to $602 billion, according to some estimates, the online sales alone were expected to jump 15.1 percent, to $61.8 billion.

“Yes, there is a Santa Claus: It’s FedEx,” said FedEx senior manager Dane Worley, overlooking the company’s regional hub at LAX, where planes full of parcels morphed into trucks full of packages fanning out across the region. “We’re fine with the extra load — that’s what we live for, that’s what we do.”

With a FedEx facility and UPS regional hub at LA/Ontario International Airport, the Inland Empire will see a peak in activity for not only Cyber Week but the holidays.

Inland Empire Economist John Husing said it is difficult to track how much of the activity will originate from this region because online retailers and packing companies don’t release their data.

“It’s important to note we are getting more and more fulfillment centers located in this region which is where those goods come from,” he said.

In 2012, compared to the previous year, the Inland Empire area gained 3,100 jobs in logistics alone, said Husing, who attributes it to the new centers and demand from consumers.

“You’re seeing rather impressive gains year-over-year and month. This is because the logistics centers have just started opening,” he said. “I can’t say the sales tax but it’s a huge employment generator.”

The U.S. Postal Service was also bracing for a banner holiday.

The nation’s largest carrier is projected to haul a record 420 million packages between Thanksgiving and Christmas. And it expects a 12 percent jump in traffic over last year even though the holiday season is a week shorter than usual because of the late Thanksgiving.

While today is expected to mark the Postal Service’s biggest online postal store rush, with 33 million orders for mostly holiday stamps, Dec. 16 is projected to be its busiest overall shipping day as residents rush to send out packages to arrive by Christmas. The day is projected to draw 6 million customers for online shipping and home pickup — about 1 million more than last year.

The Postal Service has also contracted with Amazon.com for Sunday deliveries, starting in Los Angeles and New York.

“We’re excited about this record volume,” said Richard Maher, a Postal Service spokesman in Los Angeles. “The record increase is due to online shipping, or e-commerce from such places as Amazon.com. As the Internet has taken away letter volume, it’s also increased package volume this holiday season.”

UPS has also jumped aboard the holiday bandwagon, with its busiest pickup day of 34 million packages on Dec. 16, up 9.6 percent over last year, a record. The combined 63-million package pickup and delivery total that day is also expected to be up 6.3 percent, also a record.

And its busiest delivery day of 29 million packages is expected on Dec. 17, up 5.5 percent, again a record.

“Online shopping has definitely contributed to these records,” said UPS Atlanta-based spokesman Tyre Sperling. “Our e-commerce is 40 percent for our total volume, and up 10 percent in the past six years.”

To keep up with the demand, UPS hired 55,000 seasonal workers around the U.S. for its peak season, he said.

In addition, UPS leases 23 extra jets to handle the holiday spike in volume, and adds 475 daily flights beyond the 1,900 that typically fly all over the world each day, Mangeot said.

Ontario will see some of this increased activity, he said, referring to UPS’ regional hub at ONT.

The trendsetter for holiday online shipping is Amazon.com, whose sales growth was expected to increase between 10 percent and 25 percent this quarter, compared with the same period last year.

“Last year, we had a record-breaking 306 items per second, with more than 26.5 million items worldwide on Cyber Monday, our peak day,” said Amazon.com spokeswoman Katie McFadzean. “We are expecting more this year.”